Q about new IfThen() intrinsic

[Azarien]

Ada 2012 introduced the following syntax:

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1. z:=(if b then 5 else 42);

Note that the if-expression (that's what it is called) has to be parenthesized. This solves precedence problem.

This is also legal:

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1. f:=float(if b then x else y);

which is equivalent to

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1. f:=(if b then float(x) else float(y));

When the parentheses are required anyways, no need for additional ones:

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1. func(if x then a else b);

I think Free Pascal could simply copy Ada syntax.
The rationale can be found here.

[Azarien]

Some other Ada 2012 examples:

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1. P(if X > 0 then B elsif X < 0 then C else D);
2. // we should use "else if" here
3.  
4. P(if X > 0 then (if Y > 0 then B else C) else D);
5.  
6. // special case for boolean:
7. P(if C1 then C2);
8. // same as
9. P(if C1 then C2 else True);

[marcov]

Borrowing from Ada was already discussed in the relevant threads on the maillists.

[ArtLogi]

Why ifthen() while there is Case.

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1. Case Variable of
2.   true: // do something
3.   false: // do something
4. end
5.  

.. and if CASE command doesn't allow comparisons why ifThen() doesn't use similar clear construct as case or extend the functionality of the Case Of command. (which is really nice and clear to read compared to that brainfuck IFTHEN(=?=?=?=_?= ).. Noob is wondering.

PS. If something like ifThen() is implemented why not name it to Choose() as what I can see it do just that chose the value based on the boolean comparison(or is test in programming jargon). ??

PPS.
..or

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1. Case Variable_A of
2.   true: // do something
3.   false: // do something
4.  To variable_B
5. end
6.  

..or even

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1. To variable1, variable2, variable3, variable4
2. begin
3.   case Variable_A of
4.      true: // do something
5.      false: // do something
6.   end
7. end
8.  

..or even as unorthodox as

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1. If A<>B  Then ChooseFor variable1, variable2, variable3, variable4 (*ie. list of 50 GUI elements to disable*)
2.     True: (* actions *)
3.     False: (* actions *)
4.